Question

an amoeba is a single-celled organism that feeds on algae, plant cells, and bacteria. when an amoeba feeds, it first makes contact with the food particle. next, the amoeba starts to surround the particle. once the particle is completely engulfed, it is surrounded by a layer of the amoebas membrane, forming a vesicle. the ph in the vesicle is then lowered and the contents are degraded. what type of transport is involved in this process?

a. diffusion

b. endocytosis

c. passive transport

d. exocytosis

Explanation:

• Option A: Diffusion is the movement of molecules from high to low concentration, no engulfing, so A is wrong.
• Option B: Endocytosis is when a cell engulfs large particles (like the amoeba engulfing food) by forming a vesicle, matching the process described.
• Option C: Passive transport (e.g., diffusion, osmosis) doesn't require energy and doesn't involve engulfing large particles, so C is wrong.
• Option D: Exocytosis is releasing substances out of the cell, opposite of engulfing, so D is wrong.

Answer:

B. endocytosis